Computational analyses aiding experimental testing of rocket propulsion systems have very rigorous requirements relating to turnaround time and fidelity of analyses. The performance of rocket propulsion systems is intricately tied to the functioning of valve and feed systems, since feed systems exert flow control, regulate pressure and suppress instabilities. CFD based analyses of such systems is difficult because of their structural complexity, dynamic motion of valves, coupling with related systems, the large variation in flow conditions and the inadequacy of models in handling multi-phase flow regimes that include cavitation based instabilities. Most current CFD tools based on structured grid methodology are cumbersome and inefficient to use for such problems and fail to meet the stringent requirements to support testing. The innovation proposed here is to utilize a multi-element based unstructured framework for analyses of valve based feed systems. The technology has been proven to handle geometrically complex configurations efficiently and is complemented by a suite of adaption and grid movement capabilities that allow localized high fidelity resolution and identification of important physical phenomena. Furthermore, the technology being proposed here, has evolved from a generalized multi-phase framework that allows specification of variable thermodynamic properties and physical equations-of-state appropriate to cryogenic working fluids.